26

today i noticed/realized something interesting. i probably would have never thought about this if i didnt take ap physics with you, doc. while i was walking around today, i was pushed by a really strong wind. it was so strong i had to pretty much had to lean over and gave a little more strength in each step i take. then i realized, wait a second, how does this happen and how would i calculate this bad boy. i understand air resistance because it is like friction, its just there and you know it since there must be somekind of force to against the force put in. wind, on the other hand, is an interesting force. its just there 24/7 like jack-in-the-box drive thru but depending on the days and time, the strength differs. i just wondered, how the heck does this occur. is it because earth is rotating? how would be calculate how much force a wind exerts on us? it may be quite interesting to figure those stuff out.

25

again, i will talk about track, doc. there was one thing which i noticed during a track meet. while i was watching one race, i reconfirmed myself that the speed of light is faster than the speed of sound. i was on the other side of the track when the official made a gun shot into the sky. i saw smoke coming out of his gun but i heard no sound until maybe like .3-.5 second later. it was pretty cool, i must say because when i was near the official, the smoke coming out and the sound go off at pretty much the same time. this is probably the reason why the hand time and electronic time for state qualifying time is different. because the timer is some distance away from the starting line, they would have a lag when they start their clock. it probably involves human reaction time and whatnots but whatevers. whereas, when it is done electronically, then there would be almost no lag since there is no human error involved (yay to the technologies).

24

this weekend, i caught a ride on teh bus to my track meet which was at kamehameha. while i was sitting down in the bus, i noticed couple things that were physics related stuff. for example, i noticed the usage of mirrors. there were mirrors arranged in a manner so that bus driver could see most of the things around him. another thing i noticed was the glass windows which acted like a mirror. while i took a glance at the reflected image on a window, i noticed that the image distance and object distance of the scenery were the same, which was pretty cool. also, i noticed that there were many convex mirrors so that people could see a lot of things around them. after learning how stuff works in physics, life became more fun, doc.

23

The "Mirage Mirror" is really two parabolic mirrors with identical shapes. One (mirror A (bottom)) lays face-up on the table while the other (mirror B (top)), which has a hole in its center, lays face-down on the first mirror. They are designed so that the focal point of one lies just at the vertex of the other when they are placed on top of one another. An object placed at the middle of the bottom mirror will be at the focal point of mirror on top. Light from the object reflects off of mirror B into parallel paths. This light shines on mirror A, reflects, and converges to the point fA. This light makes a real image at fA. If you look at this point, you'll see the object appear to hover at that point.

22

this weekend was very key doc. i had a track meet and wow, it was full of physics. take long jump for example, that thing is a great example for kinematic equations. a runner wants to get the greatest x velocity (speed youre running forward) and then get the maximum y acceleration/velocity (height). that's like projectile motion we learned except in the real life long jump there's wind speed, air resistance, what so ever. also, take a look at them spikes. whoever thought of using spikes must know a lot bout physics because they mustve known that more friction on your shoes makes you get the minimum energy loss through impact. another one is discuss throwing. instead of throwing it in a linear motion, they use rotational force because centripetal force and so on gives greater speed and energy to throw. the speed is the tangential speed which the discuss obtained through rotational dynamics. this is why i run track doc.

21

this week, i played drums for sr. luau and afterwards i wondered how drums worked again. last time, i was wondering about toms and snares and so on but now i started to wonder about cymbals. the drum set i used have 2 cymbal and a hi-hat which is kind of like a cymbal. one of the cymbal is called crash cymbal which is used to make a loud noise at the end of a song or the end of a fill. another cymbal is called ride cymbal which makes a high pitched sound and often used when the song is quiet and slow. hi-hat is used most often and it consists of two cymbal stacked like a pancake with a space inside (because cymbals arent flat, it has curved surface). What i wondered was, what makes these cymbals so different because none of them sounds the same. ride cymbal has the biggest surface area so when i crash it, it makes the dimmest sound. on the other hand, hi-hat though i never tried it, will most likely make the brightest sound when i crash it. but this doesnt explain why ride cymbal has the high pitched noise when i hit a different spot of the cymbal. we need to learn more physics to figure this out doc.

20

lately, i have been trying to learn how to play drums. it is quite difficult to learn but i still have joy in learning how. One day, it just happened to me and wondered, "hey, drums are perfect example to show what we have been learning this entire time!" First of all, the way drum stick bounces off the drums is the proof of newtons law and the laws of conservation of energy. the energy i put in (both potential and kinetic) to hit the drum is conserved (well not really but kind of). Because of friction, some energy must have turned into heat energy but the more energy i put in, the louder the sound becomes and faster the stick bounces back from the drum which explains this concept of cons. of energy. Also, the tension of the drum deteremines the pitch and frequency of the sound i make. The tighter drums (higher tension) give more higher pitched sound while loosened drums give off lower pitched noise. Not only i learned drums, i was able to review my physics knowledge, Doc!